Various situations exist where it is desirable to mix or interleave documents and various types of mechanisms capable of interleaving or collating documents are available. These devices tend to be bulky and associated with machines such as document copiers. These devices, however, are not suitable for high reliability applications, such, for example, as where paper currency is to be interleaved, which must be done with precision and an accurate count provided. The problem is particularly severe in situations where new "brick" currency is to be introduced into circulation. Banks and department stores are frequently the focal points of such problems. The banks are required by charter, among many other responsibilities, to place new money into circulation.
Bank cashiers and tellers have a particularly difficult time handling new currency, and bank patrons receiving the new currency may have problems as well. Various studies have been made about the problem, and it has been estimated that bank personnel counting new currency may be slowed at least 15 times the normal rate because of the tendency of the new currency to stick together. Not only is the initial counting slow, but repeated counting is necessary to avoid mistakes and loss of money. Frequently, too, the best and most reliable personnel in the bank is assigned to do this kind of work because of the importance of avoiding mistakes. Handling the new money is also a problem in that its sharp edges can result in cuts to the hands and fingers of persons handling it. The resulting increased handling on the part of the teller also causes delays which are a further cause of dissatifaction with bank service.
One way of minimizing the complaint of patrons is for a teller or cashier to hand out a combination of new and used money. Frequently, old money is interleaved between the new on a second count. Heretoforth is has been a hand operation which is tedious and time consuming.